A collection of organs that work together is called a
a. Tissue
b. Gland
c. Body system
d. Brain

Which is a direct benefit of prohibiting nicotine and tabacco use in schools?

Aperson who doesn't have enough calcium in his or her diet is at risk for developing bones that are weak and break easily. this condition is known as  a.  osteoporosis.    b.  crohn's disease.    c.  celiac disease.    d.  hemophilia.

How can a person  best  reduce the risk of injuries on the road?